1. Field of the Invention
The present invention relates, in general, to switches and, specifically, to switches mounted on the steering column of a motor vehicle for controlling a plurality of switch members connected to various vehicle operating circuits.
2. State of the Art
The evolution of steering column switches in motor vehicles has been toward greater integration of functions in a single switch. Previously, a plurality of individual switches, each controlling a single function, i.e., turn signals, were mounted on the vehicle dashboard, steering column, etc. Current steering column switches are designed to control a variety of functions or vehicle operating circuits, for example, turn signals/hazard lights, high beam and low beam headlights with optional flash to pass, parking lights, and windshield wiper and wash functions, including multi-speed wipers with or without delay.
Typically, a steering column switch includes a single lever or stalk pivotally mounted on one side of a housing attached to the steering column in an easily accessible position for the driver of the vehicle. The lever is gimballed at one end in the housing so as to move in one of two mutually separate planes. Further, the lever may be provided with a rotatable end cap as well as being slidable along its longitudinal axis. Actuators are mounted in the housing and, in response to movement of the lever in one direction, i.e., such as one of the two mutually separate planes, or rotation of the end cap, move a switching member carrying contacts between various switching positions to effect the switching of electrical connections for a particular vehicle operating circuit.
Due to the complex nature and the mechanical interconnection of the elements of the switch, including the actuators and switch members, installation, adjustment and repair costs of such steering column switches are high. The separation of the various functions of the steering column switch into sub-assemblies simplifies the design, assembly and testing of the steering column switch since each subassembly can be handled independently prior to final assembly. However, the sub-assemblies are still highly mechanically dependent upon each other in a fully assembled condition. Furthermore, such steering column switches are specifically designed for a single configuration and use. Changes in the design of any of the sub-assemblies necessitates changes in the other sub-assemblies thereby increasing design and development costs and complicating the final assembly and adjustment of the steering column switch.
In addition, each vehicle manufacturer typically manufactures a variety of different vehicle styles and models, each containing various options which necessitate separate steering column switches for each vehicle and option configuration. This adds to overall tooling costs and requires special tools and installation procedures for each specific steering column switch. Further complicating the steering column switch design is the different requirements of the U.S. and European markets for vehicle operating circuits, such as turn signals, head lamps, high and low beams, wiper/wash, etc. Since car lines are evolving into worldwide markets, different steering column switches are required to meet each different market requirements thereby increasing design and tooling costs due to the number of different configurations which are required.
Thus, it would be desirable to provide a multifunction steering column switch which overcomes the deficiencies found in previously devised steering column switches. It would also be desirable to provide a steering column switch which includes mechanically separately mounted and separately operating sub-assemblies for each vehicle operating function controlled by the steering column switch. It would also be desirable to provide a steering column switch which includes plug-in switch members which may be mounted in a variety of positions to increase the number of applications of the steering column switch. Finally, it would be desirable to provide an actuator and switch member for a steering column switch which can be easily redesigned and/or repositioned for use in steering column switches on different vehicles and vehicle configurations.